Senior Mechanical Simulation Engineer

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About OLIX

AI is growing faster than any technology in history and the explosion in demand has created a massive infrastructure gap; we can no longer build chips or power stations fast enough to keep up. The industry is still leaning on a ten-year-old hardware blueprint that has reached its limit. A new paradigm that is faster and more efficient will be the biggest economic opportunity of the next century and create the most important company of the next decade. OLIX is building this next paradigm; the Optical Tensor Processing Unit (OTPU) achieves performance and energy efficiency that is impossible to match from existing chips.

The Role:

We are seeking an experienced and motivated Senior Mechanical Simulation Engineer to lead the analysis , simulation, and optimization of precision opto-mechanical systems and advanced substrate structures critical to the performance of OLIX's Optical Tensor Processing Units (OTPUs).

This role is ideal for an engineer with a strong background in advanced simulations for structural response (both static and modal), thermal transfer, thermal expansion, optical alignment and fluid flow modeling. You will drive simulation-led development of precision assemblies and materials that meet demanding optical, thermal, mechanical, fluid flow and reliability targets.

You will collaborate closely with the mechanical, optical, electrical, and materials teams to ensure designs deliver outstanding stability, thermal performance, and structural integrity during manufacturing and operation.

Responsibilities

• Multi-physics analysis and simulations of mechanical and optical assemblies for high-performance optical and computing systems.
• Define and optimize substrate stack-ups, balancing mechanical stability, warpage control, thermal dissipation, and integration requirements.
• Conduct finite element analyses (FEA) to evaluate stress, strain, warpage, etc
• Execute thermo-optical-mechanical simulations to assess material deformation, stress evolution, and structural response under varying loads and temperatures, including effects during assembly, solder reflow, and system-level integration.
• Perform ageing and life-cycle simulations to model long-term material degradation, creep, fatigue, and stress relaxation over extended operational lifetimes.
• Lead material selection and evaluation to meet mechanical, thermal, and reliability needs - balancing CTE compatibility, stiffness, and thermal conductivity with manufacturability and cost.
• Apply expertise in substrate materials (ABF, BT, ceramics, and organics) to achieve optimized mechanical and thermal performance.
• Develop and correlate simulation models with empirical testing (e.g., thermal cycling, vibration, and temperature-humidity bias) to validate predictions and improve design accuracy.
• Collaborate across disciplines to co-optimize substrate stack-ups, thermal interfaces, and mechanical assemblies for stability and manufacturability.
• Interface with vendors and manufacturing partners to define mechanical specifications, tolerances, and material standards.
• Automate and standardize simulation workflows using ANSYS, Abaqus, or COMSOL, ensuring consistency and efficiency.
• Document simulation methodologies, assumptions, and recommendations for design iteration and technical communication.

Skills & Experience

• 10+ years of experience in mechanical analysis and simulation, ideally within opto-mechanical systems, electronics enclosures, or advanced materials applications.
• Proven expertise in substrate stack-up design - understanding of material interactions, thermal mismatch, and mechanical coupling.
• Demonstrated proficiency in advanced multi-physics simulation as well as thermo-optical-mechanical modeling for complex 3D structures.
• Experience performing ageing simulations to assess creep, fatigue, and time-dependent material behavior.
• Strong understanding of material properties - including CTE, elastic modulus, Poisson's ratio, and thermal conductivity - and their impact on performance and reliability.
• Proficiency in ANSYS, Abaqus, or COMSOL for multiphysics simulation.
• Experience with warpage mitigation, thermal management, and assembly-level stress analysis.
• Familiarity with DFM/DFR, reliability testing, and integration process constraints.
• Strong analytical, problem-solving, and communication skills with the ability to translate simulation data into design improvements.
• Master's degree in Mechanical Engineering, Materials Science, Physics, or related field; PhD preferred.

Compensation & Benefits

• Competitive Salary: £95,000 - £132,000 annual salary commensurate with your experience, skills, and location.
• Equity & Ownership: Meaningful stock options. You're not just joining the mission; you're owning a piece of it.
• Proximity Bonus: We value your time. To minimise your commute and maximise your life, we offer a £24K annual Living-Local Bonus if your residence is within 20 minutes of the office.

Health & Wellbeing

• Premium Healthcare: Comprehensive BUPA medical and dental cover, including Medical History Disregarded (MHD), for complete peace of mind.
• Time Off: 25 days of annual leave, plus all UK bank holidays.

The Workspace & Tech

• Elite Hardware: M4 Macs come as standard, with M4 Pro upgrades for our engineering team. We will provide whatever you need to do your best work.
• Optimal Environment: High-spec noise-cancelling headphones and a fully ergonomic workstation designed for deep focus.
• Rapid Prototyping: Access to our high-performance 3D printing lab for work, experimentation, and personal creative projects.

Life at the Office

• Chef-prepared meals: if you need to work late.
• Caffeine on Us: We've got you covered with a tab at our favourite local coffee shop.

Relocation & Global Mobility

• Visa Sponsorship: We hire the best in the world. We offer full UK and international visa sponsorship.
• Seamless Relocation: Whether you're moving across the country or across the globe, our dedicated relocation partner provides funding and concierge support to get you settled.

Due to U.S. export control regulations, candidates' eligibility to work at Flux depends on their most recent citizenship or permanent residency status. We are generally unable to consider applicants whose most recent citizenship or permanent residence is in certain restricted countries (currently including Iran, North Korea, Syria, Cuba, Russia, Belarus, China, Hong Kong, Macau, and Venezuela). Applicants who have subsequently obtained citizenship or permanent residency in another country not subject to these restrictions may still be eligible.